Report on geological surveys of Vrondou area

The performed research work covered Lalias subarea (A) and Ano-Kato Vrondou and Vathytopos subareas (B). In case A the investigation aimed to the delineation of a quartz vein located in a fault zone with normal high radioactivity. In order to trace the direction of the fault or secondary fault directions with similar radioactivity a grid system (scale 1:500) was set up where the following methods have been applied: scintillation counter radiometry, values of 3rd minute radon (α-radiation) measurements, proton magnetometer measurements and geochemistry with soil sampling from the grid point. Furthermore eleven trenches have been excavated from which rock samples have been taken. The results of the research are the discovery of secondary uranium bearing minerals and the determination of the fault length than was found to be 460 m; the anomalous area, with regard to radioactivity, is 60.000 m2. Detailed prospecting in the anomalous area and borehole drilling on the anomalous locations are proposed. In case B the performed work consists of stream sediment followup geochemical with radioactivity measurements on the sampling points. 756 geochemical samples have been collected from the Ano-Kato Vrondou subarea (58 km2) and 627 from the Vathytopos subarea (40 km2). The results of the geochemical analysis have shown concentrations of easily extractable uranium up to 89 ppm for the first of these subareas and up to 50 ppm for the second one